History of the Peloponnesian War

Having thus spoken, and dismissed the assembly, Archidamus first sent Melesippus son of Diacritus, a Spartan, to Athens; in case the Athenians might be more disposed to submit, when they saw that the Peloponnesians were now on their march. But they did not admit him into the city, nor to their assembly;

for the opinion of Pericles had previously been adopted, not to admit any herald with an embassy from the Lacedaemonians, when they had once marched out from their frontiers. They sent him back therefore before hearing him, and ordered him to beyond the borders that same day, and [to tell those who sent him] that in future, if they wished to propose any thing, they should send ambassadors after they had retired to their own territories.

And they sent an escort with Melesippus, to prevent his holding communication with any one. When he was on the frontiers, and was about to be dismissed, he spoke these words and departed

This day will be the beginning of great evils to Greece.

When he arrived at the camp, and Archidamus found that the Athenians would not yet submit at all, he then set out and advanced with his army into their territory.

At the same time, the Boeotians, while they furnished their contingent and their cavalry to join the Peloponnesians in their expedition, went to Plataea with the remainder of their force, and laid waste their land.

While the Peloponnesians were still assembling at the Isthmus, and were on their march, before they invaded Attica, Pericles, son of Xanthippus, who was general of the Athenians with nine colleagues, when he found that the invasion would take place, suspected that either Archidamus, because he happened to be his friend, might frequently pass over his lands, and not ravage them, from a personal wish to oblige him; or that this might be done at the command of the Lacedaemonians for the purpose of raising a slander against him —as it was also with reference to him that they had charged them to drive out the accursed; and therefore he publicly declared to the Athenians in the assembly, that though Archidamus was his friend, he had not been admitted into his friendship for any harm to the state; should, then, the enemy not lay waste his lands and houses, like those of the rest, he gave them up to be public property, and that no suspicion might arise against him on these grounds.